1. Field of the Invention
This invention relates to blower wheels and, more particularly, to blower wheels disposed within blower housings and commonly referred to as squirrel cage blowers, such as typically utilized in evaporative cooling systems.
2. Description of the Prior Art
Squirrel cage type blowers utilize a blower wheel disposed within a blower housing. The diameter of the blower wheel is slightly greater than the diameter of the air intake openings in the blower housing. The blower wheel is assembled within the housing by inserting the blower wheel into the housing from the mouth or discharge air opening of the blower wheel housing. The blower wheel is supported on a rotatable shaft which is inserted through the blower wheel after the wheel is disposed in the housing. The shaft is in turn secured to the blower wheel through a hub assembly. The shaft and blower wheel are in turn secured to a spider assembly of the housing.
The spider assembly of the housing includes bearings which support the rotatable shaft and which allow the shaft and the blower wheel to rotate. The bearings are usually flush with the outside of the housing and extend outwardly therefrom. Since the blower wheel is disposed within the housing, there is of necessity a space between the hub assembly of the blower wheel and the bearing assembly at the hub of the housing spider. This space is taken up by spacers. In most assemblies, there are two spacers, one at either end of the blower wheel, to position the blower wheel between the bearing assemblies of the housing spider so as to prevent lateral movement of the blower wheel. The hub portion of the blower wheel spider assembly usually extends inwardly from the spider assembly, and the spacer then is disposed between the exterior of the hub assembly and the housing spider.
The requirement of the spacers adds both to the expense or cost of the blower wheel and housing assembly and to the time required to the assembly process since both hubs need to be secured to the shaft and both collars need to be secured to the shaft.